Question

a study is conducted to determine if having twins is more likely to happen if a mom is a twin herself. find \\(p(\text{being a twin} \cap \text{having twins})\\). do these results suggest being a twin and having twins are independent?

results of the study

	has twins	does not have twins	total
mom is not a twin	36	89	125
total	158	342	500

• 77%; no
• 24%; yes
• 24%; no
• 33%; no

Explanation:

Calculate the intersection probability

$$ P(\text{Being a Twin} \cap \text{Having Twins}) = \frac{122}{500} = 0.244 \approx 24\% $$

Check for independence

$$
LATEXBLOCK0
$$

Determine the final option

$$ \text{Probability} \approx 24\%; \quad \text{Independent} = \text{No} $$

Answer:

• (A) 77%; No
• (B) 24%; Yes
• (C) 24%; No (Correct answer)
• (D) 33%; No